Dave,
Thanks for the response. Yes, I have been using TreeSize for quite some time now - great little Utility, even the free one I am using.
And yes, I can see space being used, but can't identify where or what the Windows Storage breakdown is identifying as "Temporary Files". Actually I found the System Storage breakdown rather accurate EXCEPT for the Temporary Files breakdown. The "Other" storage breakdown of the 231GB is fine (once I identified what was included there in the breakdown) as was the "Other people" identification (the 105GB being the size of my Admin user folder) - it is just that the 2GB breakdown of the Temporary Files size of 128GB makes no sense, and I would really like to have that space back.
I guess I will have to take the detailed analysis route, using TreeSize to add up all of the files, folders, storage that it identifies and see if it all adds up to the 746GB of storage that Windows claims I am using - or if there is some un-accounted-for missing space. I have avoided that route hoping for a much easier solution of just using Windows to delete the Temporary files.
If everything adds up, I will post it here as a failure of the System Storage utility in Settings.
And regarding your question about Delivery Optimization files, DirectX Shader, etc. - I didn't delete those as I have no idea what they were (and very small, only a few MB). the only thing I felt comfortable removing were the Temporary Internet files (2GB of the 2.18GB identified)
ron in shawnee